Essential data to inform public policy

This report presents data collected by cancer registries over the 2009–2012 period in metropolitan France. The development of a new indicator—“stage at diagnosis”—allows for the refinement of prognostic data based on the extent of the disease and provides useful information for the various work of clinicians and researchers. It will provide survival data by stage at diagnosis. Enriched with additional information on the circumstances of diagnosis, these data will help evaluate implemented policies (changes in care, trends in survival and incidence, impact of screening, etc.).

This report on the distribution of stages at diagnosis for breast, colon, and rectal cancers constitutes the first part of a broader study covering several types of cancer. It will be followed by other publications on cutaneous melanoma, prostate and thyroid cancers (late 2018), and cervical cancer (2019).

Cancers More Often Diagnosed at an Early Stage Among People Aged 40–74

This initial study provides reliable data on the stage at diagnosis for people with breast, colon, or rectal cancer. The analysis reveals:

• a higher proportion of cancers diagnosed at an early stage among people aged 40–74, the age group targeted by organized screening programs,

• a higher proportion of cancers diagnosed at an advanced stage among people aged 75 and older,

• little difference in the distribution of stages at diagnosis between men and women for colon and rectal cancers,

• a stable distribution of stages at diagnosis over the 4-year study period.

Stages at diagnosis for breast, colon, and rectal cancers

Breast cancer: only 1 in 10 cancers is diagnosed at an advanced stage

Among women, breast cancer is the most common, with more than 59,000 new cases detected each year. It is also, along with lung cancer, one of the deadliest, causing 12,000 deaths per year. Data from registries show that 6 out of 10 breast cancers are diagnosed at an early stage (limited local spread), 3 out of 10 at an intermediate stage (regional spread), and 1 out of 10 at an advanced stage. These figures remained stable throughout the study period from 2009 to 2012.

Early-stage cancers are diagnosed more frequently among those aged 50–74 (the target age group for organized screening). Two-thirds of breast cancers are diagnosed at an early stage among those aged 50–74, compared with 59% of those under 50 and 42% of those over 74. The most advanced cancers are diagnosed more frequently in women over 74.

Colorectal cancer: a similar distribution of stages at diagnosis by sex

With 45,000 new cases detected and 18,000 deaths each year, colorectal cancer is the second deadliest cancer.

Colon cancer: registry data show that over the 2009–2012 period, among patients with colon cancer, 44% had early-stage cancer and one-third had advanced-stage cancer. This distribution varies by age: cancers diagnosed at an early stage are more common among those aged 40–74 (48%), while those at an advanced stage are more common among those under 40 (38%) and those over 74 (37%). These results are similar for both genders.

Rectal cancer: The distribution of stages at diagnosis for rectal cancers is comparable to that of colon cancers, with 47% of cancers diagnosed at an early stage and 34% at an advanced stage. This distribution varies with age: more than one in two cancers is diagnosed at an early stage among those aged 15–39¹ (57%) and those aged 50–74 (51%). Cancers diagnosed at an advanced stage are more common among those over 74 (42%). These results are similar for both genders.

Surveillance based on a scientific partnership

Epidemiological cancer surveillance is based on a scientific partnership involving the French Network of Cancer Registries (Francim network), the Biostatistics Department of the Hospices Civils de Lyon (HCL), Santé publique France, and the National Cancer Institute. These four partners have established a collaborative work program that provides for the regular production of key indicators for cancer surveillance in France and addresses one of the objectives of the 2014–2019 Cancer Plan: “to support public policies with robust, shared data,” particularly through the development of new indicators such as stage at diagnosis.

View the report

¹ Colon and rectal cancers are rare before age 50: in the study, 1% were between 15 and 39 years old, and 3% were between 40 and 49 years old.